Cold work steels for cutting, punching or forming metallic materials shall fulfil a number of demands which are difficult to combine. Particularly high demands are raised upon the impact strength, especially when the tool is intended for cutting or punching adhesive materials (adhesive wear), as for example austenitic stainless steels. Further, the tool material must not be too expensive, which limits the possibility of choosing high contents of expensive alloying components.
Conventional cold work steels are well qualified in the above mentioned respects. Nevertheless, it is, however, desirable to obtain tool materials having still better features. Therefore, in some cases, there have been used powder-metallurgically manufactured high speed steels, i.e. steels which are characterized by high contents of tungsten and/or molybdenum and usually also cobalt. High speed steels, however, are expensive. Therefore, it is desirable to obtain a cold work steel without using such expensive alloying elements as tungsten and/or cobalt, at least not high contents of said elements, but nevertheless a steel having cold working features which are comparable with or better than what is achieved by means of high speed steels made through the powder-metallurgical manufacturing technique.
The wear resistance of steels can also be improved by providing the steel object with a thin coating of a very wear resistant material. Particularly, the so called CVD-technique (CVD=Chemical Vapour Deposition) gives a very wear resistant surface layer and as a matter of fact it is the most efficient method known and available today for improving the wear resistance. Unfortunately, the method also have some drawbacks which often render it impossible to use; it can be utilized only for the coating of comparatively small objects; the siz tolerances cannot be adjusted to any greater extent after the application of the CVD-coating; and it is very expensive.